Stunned cops found the trail led straight to the heart of Government.’

The plot thickens.

According to the Mail:

” One of David Cameron’s closest aides has resigned after being arrested on child pornography allegations.

Patrick Rock has been closely involved in drawing up Government policy on internet porn filters.

He quit after the Prime Minister learned he was at the centre of a police probe over images of child abuse.

Detectives from the National Crime Agency searched No 10 and examined IT systems and offices used by Mr Rock, deputy director of the Downing Street policy unit.

Mr Rock was a protege of Margaret Thatcher and has held a series of senior posts in the Conservative Party. He has been close to Mr Cameron for many years.

Described as the Prime Minister’s ‘policy fixer’, the unmarried 62-year-old had been tipped as a leading contender for a Conservative peerage only weeks ago.

His arrest and resignation from Downing Street, where he has worked since 2011, will send shockwaves through the party’s high command. The Prime Minister is said to be ‘extremely shocked’.

A friend said: ‘He has known Patrick for a long time and never expected anything like this.’

Mr Rock was arrested last month after officials at No 10 were made aware of a ‘potential offence relating to child abuse imagery’, Mr Cameron’s spokesman told the Daily Mail.

One well-placed source said Mr Rock had also been the subject of a sexual harassment complaint from a civil servant working in Downing Street, which is understood to have been passed to Mr Cameron’s chief of staff Ed Llewellyn.

‘There were accusations against him that didn’t turn into a formal process. That has upset some people at No 10,’ the source said.

Mr Cameron’s relationship with Mr Rock goes back to the Home Office, where they both worked under Michael Howard in the 1990s.

Mr Rock, who has repeatedly tried to become an MP, is known in Westminster for coining the phrase ‘Cows moo, dogs bark, Labour puts up taxes’ used by the Tories in the 1970s.

The Prime Minister brought him back into Downing Street in 2011, a move welcomed by critics as heralding the return of a ‘grown up’ to the centre of government.

In the No 10 policy unit, he has taken a particular responsibility for home affairs issues and has also been involved in drawing up the Government’s measures against internet pornography and child abuse imagery.”

The report goes on to detail how Rock was once the political correspondence secretary for Margaret Thatcher.

By a strange coincidence, much of the correspondence between Thatcher and Savile has been doctored by Mi5 under the guise of the FOI act exemption clause.

The National Archives are due to release more revealing letters from 1984, under the “thirty-year rule“, which could prove extremely damaging to the Tories in the run-up to next year’s elections.

Was Patrick Rock aware of this most sordid of correspondence?

In a further twist, a mysterious fire recently broke out at the National Archives centre in Kew and there are fears that many important documents may have been destroyed.

Is Patrick Rock’s arrest linked to these events?

Has he been arrested to serve as a warning to others in the know that they had better keep their mouths shut or else?

Will the Filthy British Establishment stop at nothing to keep a lid on their depraved secrets?